Alert archive / Kentucky / Mesoscale Discussions in 2012
Mesoscale Discussion 591
The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2012, 1:23 PM CDT for 67 counties in Kentucky; 23 counties in Tennessee. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 26, 2012, 1:23 PM CDT (18:23 UTC)
- Expired
- Apr 26, 2012, 3:30 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 90 counties
Adair County, KY, Allen County, KY, Barren County, KY, Bath County, KY, Bell County, KY, Boyd County, KY, Boyle County, KY, Breathitt County, KY, Butler County, KY, Caldwell County, KY, Calloway County, KY, Carter County, KY, Casey County, KY, Christian County, KY, Clark County, KY, Clay County, KY, Clinton County, KY, Cumberland County, KY, Edmonson County, KY, Elliott County, KY, Estill County, KY, Floyd County, KY, Garrard County, KY, Graves County, KY, Green County, KY, Greenup County, KY, Hart County, KY, Jackson County, KY, Jessamine County, KY, Johnson County, KY, Knott County, KY, Knox County, KY, Larue County, KY, Laurel County, KY, Lawrence County, KY, Lee County, KY, Leslie County, KY, Lincoln County, KY, Logan County, KY, Lyon County, KY, Madison County, KY, Magoffin County, KY, Marion County, KY, Marshall County, KY, Martin County, KY, McCreary County, KY, Menifee County, KY, Metcalfe County, KY, Monroe County, KY, Montgomery County, KY, Morgan County, KY, Muhlenberg County, KY, Owsley County, KY, Perry County, KY, Powell County, KY, Pulaski County, KY, Rockcastle County, KY, Rowan County, KY, Russell County, KY, Simpson County, KY, Taylor County, KY, Todd County, KY, Trigg County, KY, Warren County, KY, Wayne County, KY, Whitley County, KY, Wolfe County, KY, Cheatham County, TN, Clay County, TN, Davidson County, TN, DeKalb County, TN, Dickson County, TN, Fentress County, TN, Henry County, TN, Houston County, TN, Humphreys County, TN, Jackson County, TN, Macon County, TN, Montgomery County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Robertson County, TN, Scott County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Williamson County, TN, Wilson County, TN
The radar
The Louisville radar (KLVX), 91 km from the middle of the area, began a volume at 18:26 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 12:00Z, 6.4 hours before the alert went out and 162 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 824 J/kg
- Mixed-layer CIN
- -212 J/kg
- Mixed-layer LCL
- 986 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km storm-relative helicity
- 317 m²/s²
- 0-3 km storm-relative helicity
- 344 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 9.1
The text
As transmitted, in the capitals the NWS used until 2016.
242
ACUS11 KWNS 261823
SWOMCD
SPC MCD 261823
KYZ000-WVZ000-OHZ000-VAZ000-TNZ000-ILZ000-262030-
MESOSCALE DISCUSSION 0591
NWS STORM PREDICTION CENTER NORMAN OK
0123 PM CDT THU APR 26 2012
AREAS AFFECTED...SRN/ERN KY...NRN TN
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 261823Z - 262030Z
TSTMS SHOULD INITIATE ALONG A WEAKLY CONVERGENT COLD FRONT DROPPING
SEWD ACROSS KY. A MODERATELY UNSTABLE AIR MASS AMIDST STRONG
DEEP-LAYER SHEAR WOULD BE FAVORABLE FOR SUPERCELLS/ORGANIZED
CLUSTERS PRIMARILY PRODUCING LARGE HAIL AND LOCALLY DAMAGING WINDS.
THE PROBABILITY OF A WW ISSUANCE IS 80 PERCENT BY 20Z.
18Z SURFACE ANALYSIS PLACED AN ARCING COLD FRONT FROM NEAR UNI TO 20
S LEX TO PAH. SURFACE WINDS HAVE LARGELY VEERED TO W/SWLY IN THE
WARM SECTOR...LIMITING CONVERGENCE ALONG THE BOUNDARY. BUT CU APPEAR
TO BE INCREASING IN THE FRONTAL ZONE...AND ASCENT SHOULD BE AIDED BY
A WEAK MID-LEVEL IMPULSE/SPEED MAX MOVING SE ACROSS THE MIDWEST/OH
VALLEY. ABUNDANT STRATOCU HAS RESULTED IN BROKEN TO OVERCAST CLOUD
COVERAGE OVER MUCH OF TN AND EXTREME SRN KY. BETWEEN THIS STRATOCU
DECK AND THE FRONTAL ZONE WOULD BE THE MOST LIKELY ZONE OF TSTM
INITIATION IN THE NEXT COUPLE OF HOURS. WITH A BROAD SWATH OF LOWER
TO MIDDLE 60S SURFACE DEW POINTS...MLCAPE OF 1500 TO 2500 J/KG IS
PREVALENT. GIVEN EFFECTIVE SHEAR AROUND 40 KT...THIS SETUP SHOULD
YIELD A FEW SUPERCELLS/ORGANIZED CLUSTERS PRIMARILY PRODUCING LARGE
HAIL ALONG WITH LOCALLY DAMAGING WINDS.
..GRAMS/THOMPSON.. 04/26/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...RLX...MRX...JKL...ILN...LMK...OHX...PAH...MEG...
LAT...LON 36698874 37088851 37398633 37798485 38558332 38578279
38408254 38028241 37738243 36628354 35848606 35938750
36288858 36698874SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 10:11 PM CDT | Mesoscale Discussion | SPC | Anderson, Bath, Boone, Bourbon, Boyd, Boyle and 72 more | 2 hr |
| Apr 26, 12:40 AM CDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Anderson, Barren, Bourbon, Boyle and 53 more | 6 hr |
| Apr 26, 2:23 AM CDT | Mesoscale Discussion | SPC | Anderson, Barren, Boyle, Breckinridge, Bullitt, Butler and 30 more | 97 min |
| Apr 26, 4:07 AM CDT | Mesoscale Discussion | SPC | Bell, Clay, Knox, Laurel, Leslie, McCreary and 1 more | 83 min |
| Apr 26, 5:22 AM CDT | Severe Thunderstorm Watch | SPC | McCreary, Wayne, Whitley | 3 hr |
| Apr 26, 6:24 AM CDT | Mesoscale Discussion | SPC | Bell, Harlan, Leslie, Letcher, Perry | 96 min |
| Apr 26, 2:11 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Barren, Bell, Breathitt, Calloway and 42 more | 6 hr |
| Apr 26, 3:22 PM CDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bell, Breathitt, Clay and 26 more | 83 min |
| Apr 26, 5:40 PM CDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bell, Breathitt, Clay and 23 more | 95 min |
| Apr 26, 7:10 AM CDT | Severe Thunderstorm Watch | SPC | Bradley, Hamilton, Polk | 3 hr |
| Apr 26, 7:47 AM CDT | Mesoscale Discussion | SPC | Blount, Bradley, Carter, Johnson, Loudon, McMinn and 6 more | 88 min |
| Apr 26, 4:52 PM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Chester, Crockett, Decatur, Dickson and 13 more | 83 min |
| Apr 26, 6:09 PM CDT | Mesoscale Discussion | SPC | Bradley, Polk | 96 min |
Nearby
Mesoscale Discussions in Kentucky, 2012Mesoscale Discussions in Tennessee, 2012Every mesoscale discussion in 2012
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.